FLU WARNING: Virus MUTATION sparks vaccination crisis

AS the number of influenza cases worsens in the United States, the World Health Organisation has warned vaccination manufacturers are facing an ongoing struggle to keep pace with viruses which mutate constantly.

Related articles

The number of people being hospitalised as a result of flu in the season 2017/18 is outstripping that of 2014/15, which itself was a particularly severe outbreak, according to experts at the Centre for Disease Control’s (CDC) headquarters in Atlanta, Georgia.

53 children have died from flu in the US this season as vaccines struggle to combat different strains of the virus.

CDC director Anne Schuchat said: "I know many of you are concerned about this flu season and have seen the heartbreaking stories of those who have lost loved ones.

"This week, we are reporting an additional 16 flu related pediatric deaths for this season. Meaning there are even more families now devastated by flu.

GETTY

The World Health Organisation says rapid rates of mutation poses a challenge for doctors

"That means we’ve received reports for a total of 53 children who have died of the flu so far this season.”

Mrs Schuchat said one of the main problems is most vaccines are relatively ineffective against H3N2 strains which is currently most prevalent in the US.

She said: “Effectiveness against other flu viruses is better, and there is more than one flu virus circulating this season.

“The virus may also reduce the severity of symptoms of you catch the flu in spite of being vaccinated.”

Her colleague, Dr Dan Jernigan, warned: “We’re still seeing significantly higher hospitalisation rates in some states and while reports of new hospitalisations were lower in the last week, the cumulative hospitalisation rates in California, for example, are again about four times higher than they were in 2014-’15 and in Oregon and Minnesota, they are double what they were double what they were in 2014-’15.

“We also have information about paediatric deaths due to influenza, and we receive those reports each week."

Speaking after the news conference, WHO spokesman Yan Jin confirmed that H3N2 strains are dominating in the US this influenza season.

Centre for Disease Control

This graphic shows the number of cases in 2017/18 in the US in comparison with other recent years

'This low vaccine effectiveness in Australia and Canada might be due to the mutations that influenza viruses can undergo when being grown in eggs for production of the influenza vaccine.'

WHO spokeswoman Yan Jin

She said: “Influenza A/H3 influenza viruses are known to be associated with higher morbidity and mortality than H1 and B viruses; and during H3 predominant seasons, we see increases in disease burden [the impact of a health problem as measured by financial cost, mortality and other indicators].”

If vaccination effectiveness estimates against H3N2 strains were accurate, as was seen in Australia following the outbreak of the so-called Aussie flu, this would explain the high disease burden, she said.

She said: “This low vaccine effectiveness in Australia and Canada might be due to the mutations that influenza viruses can undergo when being grown in eggs for production of the influenza vaccine.

“These egg-adaptations during vaccine production can lead to decreased match between the circulating viruses and the viruses in the vaccine.”